Sqlite- Updating existing table

I am trying to update sqlite Table using execSQL. But, After executing it is clearing(empty) my whole table data instead of updating certain fields. My code is

private void updatedata(String name,String spingender,String cWeight,String spinunit,String htInString,String spingoal,String spinactivity,String spinexercise,String scalorie,String sprotein,String carbohydrate,String sfat) {

        DatabaseHandler helper = new DatabaseHandler(getApplicationContext());
        SQLiteDatabase db = helper.getReadableDatabase();
        System.out.println("in update data "+name + spingender + cWeight);
        String Query = "SELECT * FROM login WHERE name ='"+name+"'";
        Cursor QueryCursor = db.rawQuery(Query,null);

        // there is some record available in the cursor 
        if (QueryCursor.moveToFirst()) {
                 db.execSQL("UPDATE login SET gender='"+spingender+"',weight='"+cWeight+"',userunit='"+spinunit+"',height='"+htInString+"',goal='"+spingoal+"',activeness='"+spinactivity+"',exercise='"+spinexercise+"',calorie='"+scalorie+"',fat='"+sfat+"',carbohydrate='"+carbohydrate+"',protein='"+sprotein+"'");            
        }

        QueryCursor.close();
        db.close();
    }